<--- for when/if people go into more technical aspects in a reply. 
.040 Head gasket=more HP?
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On The Tree
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From: Tampa,Fl
.040 Head gasket=more HP? I've heard that by using a .040 Cometic head gasket on a stock LS1 it will increase the compression. If so by how much. Is it worth the hassle? Engine is internally stock 02' Vette 
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A thicker head gasket will decrease and a thinner will increase compression but I dont see it making much of a hp diff.You may increase your chance of detonation and damage to your stock engine though.
Last edited by lovescamaros28; May 1, 2007 at 02:35 PM.
You shouldn't increase your chance of detonation, but rather decrease it with the tighter quench. Yes, it would be a small increase in power production, but if you weren't taking the heads off for another reason, it would not be worth it.
A thinner gasket on higher compression motors will actually be more immune to detonation than a thick head gasket with everything else held the same. Example; installing a thicker head gasket to decrease compression because of detonation can actually make the problem worse. There is a certain range you want your quench to be in. A larger quench will not help over a tight one until quench gets notable higher.
Ben T.
A thinner gasket on higher compression motors will actually be more immune to detonation than a thick head gasket with everything else held the same. Example; installing a thicker head gasket to decrease compression because of detonation can actually make the problem worse. There is a certain range you want your quench to be in. A larger quench will not help over a tight one until quench gets notable higher.
Ben T.
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Originally Posted by Studytime
You shouldn't increase your chance of detonation, but rather decrease it with the tighter quench. Yes, it would be a small increase in power production, but if you weren't taking the heads off for another reason, it would not be worth it.
A thinner gasket on higher compression motors will actually be more immune to detonation than a thick head gasket with everything else held the same. Example; installing a thicker head gasket to decrease compression because of detonation can actually make the problem worse. There is a certain range you want your quench to be in. A larger quench will not help over a tight one until quench gets notable higher.
Ben T.
A thinner gasket on higher compression motors will actually be more immune to detonation than a thick head gasket with everything else held the same. Example; installing a thicker head gasket to decrease compression because of detonation can actually make the problem worse. There is a certain range you want your quench to be in. A larger quench will not help over a tight one until quench gets notable higher.
Ben T.
I think you need to research compression ratio,detonation,and pre-ignition and what causes spark knock.Higher compression ratios increase the chance of abnormal combustion(detonation)compared to lower compression ratios.I am sure you know that static compression ratio is the volume of the cylinder at bdc compared to the volume of the combustion chamber area at tdc.Detonation is an explosion that happens after the normal spark from the spark plugs occurs.Increased compression ratio results in more performance,better fuel econonmy,but also increases emissions and abnormal combustion from higher temeratures and increased mechanical energy potential.Why do you think we reduce compression ratios when running over a 250 shot of nitrous?Higher compression is asking for failure.In addition,why do you think high octane fuel(octane=a fuels ability to resist explosion or detonation)is recommended with high compression engines?Pretty self -explanatory.In conclusion,if you want to install a very thin head gasket to boost CR ratio without any ECM tuning go right ahead but dont say I did not warn you.
Originally Posted by lovescamaros28
I think you need to research compression ratio,detonation,and pre-ignition and what causes spark knock.Higher compression ratios increase the chance of abnormal combustion(detonation)compared to lower compression ratios.I am sure you know that static compression ratio is the volume of the cylinder at bdc compared to the volume of the combustion chamber area at tdc.Detonation is an explosion that happens after the normal spark from the spark plugs occurs.Increased compression ratio results in more performance,better fuel econonmy,but also increases emissions and abnormal combustion from higher temeratures and increased mechanical energy potential.Why do you think we reduce compression ratios when running over a 250 shot of nitrous?Higher compression is asking for failure.In addition,why do you think high octane fuel(octane=a fuels ability to resist explosion or detonation)is recommended with high compression engines?Pretty self -explanatory.In conclusion,if you want to install a very thin head gasket to boost CR ratio without any ECM tuning go right ahead but dont say I did not warn you.
Originally Posted by twospeed
I've heard that by using a .040 Cometic head gasket on a stock LS1 it will increase the compression. If so by how much. Is it worth the hassle? Engine is internally stock 02' Vette
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Yes,I just did a little more research.I apologize he had a very good point.It does sound kinda contradictory to think that increasing CR can actually reduce detonation due to a tigher squish/quench area,but I found out I may have been the one that was slightly mis-informed.I do understand turbulence resulting in more complete combustion so it does prove a point.Here is a good link I found that kinda proved me to be wrong.http://www.chevyhiperformance.com/te...earance_guide/
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Originally Posted by lovescamaros28
Yes,I just did a little more research.I apologize he had a very good point.It does sound kinda contradictory to think that increasing CR can actually reduce detonation due to a tigher squish/quench area,but I found out I may have been the one that was slightly mis-informed.I do understand turbulence resulting in more complete combustion so it does prove a point.Here is a good link I found that kinda proved me to be wrong.http://www.chevyhiperformance.com/te...earance_guide/
Tight quench completely gets rid of the hot spots in the chamber that lead to detonation. That is a direct result of the homogenous mixture, its a even mix all through the chamber.
Some things just seems *** backwards to common knowledge but are right. Ive been preaching tight quench for a while now.
Funny... On another site/forum I got into a discussion with a very stubborn fella that still maintains to this day that a wise and (his) recommended measure to reduce compression (and thus in his mind reduce the chance of deto) was to swap the factory .054" gasket with .072" Cometics...and that he's done so on his 500rwhp/tq BOOSTED (10psi) Magnacharged LS2 as proof that it "works"... Yet no matter what facts were shared with him from online references, engine handbooks, reputable builders, my old engineering textbooks, etc., his refusal to believe (understand?) the role/impact/benefit of proper quench was becoming downright sad....
Still, I should have known beforehand that it was going to be a winless thread... He also still believes that he makes 415 Hp and 430 Tq at 3100rpm. (The mathematical calculation between Hp and Tq for him doesn't apply...)
Lovescamaros28 - its great to see that you kept an open mind and sought out the proper information...and was willing to admit that you learned something! (far too often people are too proud to admit such a thing!)
Still, I should have known beforehand that it was going to be a winless thread... He also still believes that he makes 415 Hp and 430 Tq at 3100rpm. (The mathematical calculation between Hp and Tq for him doesn't apply...)
Lovescamaros28 - its great to see that you kept an open mind and sought out the proper information...and was willing to admit that you learned something! (far too often people are too proud to admit such a thing!)
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Thanks,eventhough I have plenty of automotive knowledge,it is always nice learning from people who have more knowledge than you on a particular subject.People who refuse to admit they are wrong will never learn anything.Studytime seems to be very knowledgeable.I could probably learn a lot from him and other people.
